Bacterial adherence to mucosal surfaces is considered to be an important prerequisite for colonization and infection. A variety of molecules and macromolecular structures, collectively known as adhesins, binding entity coming from the bacterium, recognized and interact with receptors on the surface on the host cells.
Three principal types of adhesin-receptor interactions have been described. The first type of adhesive interaction is due to the binding of lectins with carbohydrate structures. The second type, of which a significant number of cases are known, involves recognition between a protein on the bacterium and a complementary protein on the mucosal surface. The third type, comprises the binding interactions that occur between hydrophobins, frequently involving hydrophobic moieties of proteins interacting with lipids.
The first type, the lectin adhesins are usually classified by sugar specifity. Specifity can be determined by inhibiting the adhesion with either simple or complex carbohydrates that compete with the binding of the adhesins to host cells.
Sharon et al. in the document “Bacterial adherence to cell surface sugars”, Ciba Found Symp. 1981, vol.80, pp 119-41, describes that the attachment strains of Escherichia coli and Salmonella spp. to epithelial cells is inhibited by D-mannose. Unfortunately the active mannose concentration necessary to produce inhibition, is high, al least about 0.5 M. Escherichia coli is among the most common causes of diarrhea, to receptors on intestinal epithelial cells. Escherichia coli may colonize, too, the vaginal and periurethral area and ascend the urinary tract. Its adhesion to the epithelial cells is the initial step in the establishment of infection. Thus, the ability to attach to the mucosal surface is thought to be essential for Escherichia coli to colonize and to remain in the urinary tract.
The document, Jose A. Castillo et at “Fructose-6-phosphate aldolase in organic synthesis: preparation of D-Fagomine, N-alkylated derivatives, and preliminary biological assays” Organic Letter 2006, vol. 8, no26, pp. 6067-6070, describes that D-fagomine and the N-alkylated derivatives C4, C6, C8, C9 and Ph-CH2 do not show antimicrobial activity.
Other type of inhibitors are iminocyclitols also called iminosugars or azasugars. The document, Barira Islam et al. “Novel anti-adherence activity of mulberry leaves: Inhibition of Streptococcus mutans biofilm by 1-deoxynojirimycin isolated from Morus alba”, Journal of Antimicrobial Chemotherapy 2008, vol. 62, pp. 751-757, describes the anti-microbial activity against S. mutans of 1-deoxynojirimycin, compound isolated from M. alba. DNJ is a glucosidase inhibitor. Unfortunately, these glucosidase inhibitors often cause intestinal discomfort and diarrhoea.
Other botanical extract are described in the following patent applications.
The patent application US20090087501 provides an oral composition having at least two botanical active ingredients derived from plants. The botanical active ingredients provide particularly efficacious antimicrobial, antioxidant, anti inflammatory, antiageing and/or healing properties to the oral composition.
The Japanese patent application JP19920073844 describes a toothpaste comprises an extract of Kuwahakubi and an extract of Morus Alba. 
The Japanese patent application JP20070230719 describes an immunostimulant comprises water soluble extract of bark of mulberry, as an active ingredient.
The document Asano et al. “N-containing sugars from Morus Alba and their glycosidase inhibitory activities” Carbohydrate Research 1994, vol. 259. pp. 243-255, describes the N-containing sugars from the roots of Morus Alba, and the glycosidase inhibitory activities of these compounds.
Finally the patent application CA2696874 describes an effective fraction of alkaloids prepared from mulberry twig, and the pharmaceutical composition containing the effective fraction for preparing hypoglycemic agents.
Other documents describe sugars or imino sugars for different pharmaceutical applications. The patent application WO2009152665 describes a pharmaceutical composition comprises fagomine for treating and preventing diabetes. The patent application WO2010029313 describes alkaloids and imino sugars with activity against HCV (Hepatitis C virus) and RSV (respiratory syncytial virus). The patent application WO03002127 describes the use of a glycoinhibitor substance comprising a pyranose structure with at least one oligosaccharide for treatment an infectious disease.
Finally the patent application EP0852948 describes the use of inhibitors of glycosidase enzymes, such as α-galactosidase, in the treatment of malaria, endotoxic shock and septic shock. The inhibitors reduce the conversion of the toxin precursor to toxin, thereby reducing the amount of toxin circulating in malaria patients.
Thus, from what is known in the art, it is derived that the development of inhibitors of the bacterial adherences is still of great interest.